This invention relates to protecting electrical device assemblies, such as switches and receptacles, during installation behind wall surfaces, and to methods of finishing walls containing such devices.
To facilitate field installation of wall-mounted electrical devices, such as electrical receptacles and switches, many such devices are now provided as pre-wired assemblies in which the device is mounted and wired within a standard junction box from which wires extend in a conduit whip for connecting the device to the rest of the branch circuit. Thin plastic covers are sometimes taped in place over the devices during assembly to protect against dust and paint during wall trimming.
Such device assemblies are mounted directly to internal wall supports prior to the installation of the wall facing material, such as drywall. Prior to hanging the sheet of drywall about the front of the device, a rectangular hole is cut at a measured location through the drywall to expose the device in the finished wall. Proper positioning of the drywall hole is critical to ensure that the hole will be completely covered by the cover plate installed over the device once the wall has been finished. With the hole cut, the drywall is hung, taped and finished. Once wall finishing and painting are complete, the thin plastic dust cover in place is removed from the device and the cover plate is installed.
Any improvement in the speed with which walls can be safely trimmed out can result in significant job-site cost savings.